Report on Arctic Marine Pollution

3. Brief overview of the state of the Arctic environment

There is general agreement that the Arctic marine area and its flora and fauna are relatively unpolluted compared to other marine areas. Most of the biological production takes place in the upper 200 metres. This layer is dominated by inflowing water from the Atlantic Ocean. This inflow and the inflow from the Pacific Ocean together constitute 98% of the input, while rivers account for the rest.

There are two important exceptions to the statement that the Arctic marine area is relatively unpolluted. The first is substances which in seawater may accumulate from low concentrations to raised concentrations in plants and particularly in animals due to special pathways and subsequent bioaccumulation. These substances are primarily POPs and mercury which are often transported at long range from the northern hemisphere.

The other exception is local sources or sources with emissions to the Arctic environment, particularly in the Russian part of the Arctic region. In many cases identification of sources is a prerequisite for combating such contamination.

The following groups of pollutants have been found in the Arctic marine environment in concentrations requiring action: POPs, heavy metals, radioactive material, oil and PAHs.

These substance types or groups require action because in certain cases they threaten the Arctic flora and fauna, and because of their adverse impact on the health of groups of people with a large proportion of marine foods in their diet. However, scientists agree that any negative effects of the traditional Arctic diet are offset by the positive elements of the diet.

POPs: present and historical use of POPs (persistent organic pollutants) in the northern hemisphere is the main source of these substances in the Arctic marine environment. Raised POP levels have been found at several locations north of Canada, at Svalbard, Eastern Greenland and in the Barents Sea. However, the POP levels in Arctic marine animals are generally lower than in comparable animal species from temperate regions. Nevertheless, the content of PCB and dioxins/furans in a number of Arctic marine mammals and birds is at or above known impact levels. The distribution of pollution in the Arctic environment clearly illustrates the importance of components transported at long range. A general effort to combat long-range transmission of POPs, and a more targeted effort against local sources, are thus required.

Metals: heavy metals are a natural element of the marine ecosystem, but they are also added from human activities. The primary causes of concern in the Arctic environment are mercury (Hg), as well as cadmium (Cd) and lead (Pb). Mercury is carried in the air or in sea currents from the industrialized areas in temperate regions. In general the metal levels in Arctic marine areas are at the background level, except near local sources. However, in many parts of the Arctic region the cadmium levels in marine organisms exceed the global level, while the mercury levels are high, but not above the global level. This is a problem for the groups of people with a high intake of marine foods. In the Russian area in particular raised levels of heavy metals have been found locally.

Radioactive material: radioactive contamination of the Arctic area is low, but present and historical activities entail a risk of large-scale future contamination. The primary sources of the present pollution are fallout from past nuclear weapons tests and European reprocessing plants. The latter's emissions have decreased, although new releases of Technetium-99 from Sellafield in the UK are a cause of concern. Two potential future sources are nuclear reactor accidents - in connection with daily operation or handling of waste - or leakage from waste stored on dry land or from dumped reactors or waste. The latter applies particularly to the Kara Sea.

Oil and PAHs: with the exception of areas with local permanent impacts or areas affected by oil spills the input of oil in the Arctic marine environment is low, and no ecological damage has been established. The highest levels are found at estuaries. Furthermore, a certain amount of oil is transported at long range, particularly in the atmosphere. Raised PAH levels have been found at several locations in the Arctic marine environment.

Although the Arctic marine areas are generally less polluted than other marine areas the discoveries of raised concentrations of POPs as well as cadmium and mercury threaten the peoples with a large proportion of marine foods in their diet.